Knife sharpener



June 16, 1931. W F POLSON 1,810,727

KNIFE SHARPENER Filed April 5, 1927 Patented June 16, 1931 WILLIAM r. roIisort-on-BUFFALO, NEwYonx KNIFE' SHARPENER Appncatign mea April 5, 1927. seriai Na laines.Y

My invention relates to improvements in knife sharpeners of the type having two sets or gangs of disks, marginally overlapped. One of the objects of my invention is to provide afknife Sharpener of extremely sim'- ple construction and high efficiency, and one especially adapted for household use for quickly and conveniently sharpening rcuttingimplements.

Another object lof my invention is to provide asharpening device equipped with two sets or gangs of cutting disks centrally supported and preferably held against rotation, except under force circumferentially*l applied. y

-A further object of my invention is to provide a sharpening deviceof-the kind mentioned in which the disks of the two sets or v gangs are permanently disposed at a slight yangle to each other and are so maintained,

the'disksbeing held against wobbling or tiltingmovement by spaced elements betweeny which each 'gang is positioned.

v'A' still furtherobject of Vmy Invention is to provide a knife sharpener of the kind mentioned`in which'the support includes two spaced parallel spindles .and twospaced supporting members in which the end portions l of the spindleslare securely fastened, each supporting member having 'portions at a slight angle to each other, and two sets or gangs of r"marginally overlapped Sharpener disksmounted onv said spindles'betweenfthe angularlyedisposed"portions of said end supi5 porting members so that the spindlesof the two setsor gangsc are at slight angles and clamped between the angularly disposed por-V tions ofsaid supporting members so Vas to bel held against rrotation on said spindles,fex

40 cept'under the application ofpressure ap plied thereto circumferentially for Y the purpose ofl presenting ,new portionsk of thecuttinge'dges to a knife or other blade 'to be sharpened.` s

The advanta gesy yand* details of construction bymeans of which these objects are vattained willbe described hereinafter. Y

My invention consists in the novel features of construction and inthe arrangementand '50 combination of partsto be hereinafter de,

scribed and'more particularly pointed outin the subjoined claims.

In the drawings Fig. 1 is a side elevation of thel device. Fig. 2 is a cross4 section taken' on line2-2, l Fig.1.` s l n Fig-3 is 'a plan view ofthe device,v a por-y tion of thehandle beingbroken away."

` Figgl is a detached Aperspective view of the frame or body portion ofthe device.

` Fig. 5 isa longitudinal section taken von line 5-5, Fig. 3. y v ,'Fig. 6 is an enlarged horizontal section taken on line 6-6, Fig. 1. 'j Fig. 7 is an enlarged section taken on line 7-7, Fig.`5, the section being through one of the supporting members yof Athe device andy through portions of two sharpening disks showing the manner in which said disks are rotatably but non-tiltably mounted.

' vReference being had to the drawings in detail, the numeral 8 designates the frame .or

support ofthe device, 9 and 10 the two sets or gangs of sharpening elements in the form ofdisks, and 1,1 the handle; The frame or support of the device 4 is vpreferably constructed of a'single piece of sheet metal bent to provide a flat bottom 12, opposite upstanding sides 13, 14, which may also be referred to as supporting members, utilized for a pur pose to appear hereinafter, inwardly and upwardlyminclined supporting arms 15, 16 eX- tending,`respectively, from the inner ends of said supporting members, and overlapping extensions 17, 18 on said .supporting arms Ydisposed in opposite"directio11s soasto overlap and contact with eachother, said eXtensfions havingjvalined openings 19 through Y parallel spindles 24,' 2.5 SUP?y porting members are made slightly angular, and more particularly describing the same, one of said supporting members is inclined inwardly from opposite ends while the other is inclined outwardly from opposite ends, this being accomplished by means of a die or dies applied to said members to force one inwardly at a point centrally between its ends while maintaining the ends in iiXed position, and to force the other outwardly at a point midway between its ends, also while maintaining the ends of the same in fixed position. In this manner the openings formed in said end supports at opposite sides of the frame or supp-ort are maintained in alinement so that when placing the spindles 24 and 25 within the frame of the device, theyA will be positioned in parallelism. It is particularly to be pointed out that the upper portions only of the supporting members are inclined while the lower portions adjacent the bottom l2 of the frame are substantially parallel, as clearly sh-own in Fig. 3.

It is of course understood that before positioning the spindles within the alined openings 22 of the supporting members, the two sets or gangs of Sharpener disks 9 and lO are mounted thereon, and after. placing the spindles with their supported Sharpener disks in position, the ends of the spindles are headed in any suitable manner, as at 26.

The Sharpener disks illustratedhave their marginal portions overlapped, as at 27, which is permitted by reason of the fact that spacing elements 28 are utilized to separate the marginal portions of the disks of each set or Ygang* from each other, and while I have shown the spacing elements formed integral with the Sharpener disks, it will be apparent that separate washers may be interposed between said disks in a manner now commonl employed in knife Sharpeners of the multiple disk type.

In the drawings, thespacing el'ements are formed by pressing the central portion of each sharpener disk outwardly from one side thereof, forming thereon a 'substantially central spacing boss. The disks are reversed in opposite sets or gangs and the marginal portions of each set or gang overlaps the marginal portions of the other in transverse alinementpwith the notches 2l formed in the frame or support, thus forming a substantially V-shaped blade-receiving space 29- in line with said notches into which space the knife blade or other implement to b e sharpcned is adapted to be placed in contact with the disks. l

These sharpener disks have openings 30 formed centrally therein through which Vthe spindles 24 and 25 are passed, and these openings are a trifle larger in diameter than the diameter of said spindles'so that when positioned between the sides of the frame they are clamped therebetween upon heading the ends of the spindles, and thus held against wobbling or tilting movement on the spindles, due to the fact that the corners 3l, formed by the walls of the openings in the Sharpener disks joining the inner sides of the spacing bosses are in firm Contact with the spindles on which they are mounted, while the corners 32 of said walls joining the outer sides of said spacing bosses are in rm contact with said spindles at diagonally opposite points. While the supporting members of the frame serve to prevent wobbling or tilting of the disks on their supporting spindles, the fact that these disks have firm support on the spindles also prevents wobbling or tilting movement.

It is, of course, understood that the sharpener disks are rotatable on the spindles under stress applied circumferentially so that different points of the marginal portions of the disks can be brought to the cutting plane or bight of the V-shaped blade-receiving space 29 formed by the overlapping disks. It is also apparent that by reason of thesel disks having the walls of their central openings bearing against the spindles at diagonally opposite points, and also by reason of the fact that the disks are positioned between the supporting members of the frame without play and the upper portions of said supporting 'members are inclined outwardly from their ends at one side and inwardly at the other, that said Sharpener disks of the two sets or gangs are disposed at a slight angle to each other, with the result that the peripheral edges of one set or gang of disks are disposed at a slight angle to the peripheral edges of the other set or gang, and when positioning the blade of a knife in the bight of the V-shaped blade-receiving space and drawing said blade lengthwise in one direction, the corners formed by the peripheral edges and the receding sides of the cutting disks act against the knife blade to sharpen the same, the sharpening corner of all the disks being in effective operation under such conditions and preventing the formation of irregularities otherwise caused by removing somewhat larger portions of the'knife blade along certain parts thereof than would be removed along other parts. While the sharpening disks are rotatable upon their spindles they areynot freely rotatable, although under the principle involved, with exact workmanship, said sharpener disks can be made to rotate freely and still be non-wobbling or non-tiltably arranged. However, las a knife Sharpener of this type is adapted for household use and must therefore be produced at a small cost, I prefer to so Vconstruct the device that the cutting disks are rotatable only when applying stress or force thereto circumferentially.

The essence of this invention-resides in disposing the sharpening disks in marginally f overlapped sets or gangs arranged at a slight spaced supporting walls, and two sets `of mar-- ginally-s aced sharpening disks on said spin"- angle to each other, and in maintaining the Y angular disposition thereof; and to accom plish this in which I consider the'preferred Y arrangement it is only necessary to force out or advance the upper portion of one of the upstandingsides or supporting members cen` trally between its ends and force inwardly or cause the other upstanding side or supporting member to recede at a point centrally between its ends, so that one-half the length of each upstanding side or supportingmei -VV .ber is at a slight angle to thel'othe-r half along its upper portion, each inclined portion of one upstanding side or supporting member being parallel with the corresponding portion of the other upstanding side or supporting member.

It is highly essential th at the degree of overlap of the two sets or gangs of disks along the bight ofthe V-shaped blade-receiving space 29 sliallbe alike from one side of the device to the other, or more particularly from one end of the two sets or gangs of disks to the other end thereof, and for this reason the spindles 24,25 should be arranged in parallelism and provision made for allowing'the cutting disks to vbe angularly disposed upon the spindles while maintained against` wobbling or tilting movement.

Having thus described my invention, what I claim is 1. A knife sharpener, comprising a support, ried by said support, a set of sharpening disks on each spindle marginally overlapping the set on the other spindle, and means embodied in the construction of the knife Sharpener to permanently hold the set of disks on one spindle in angular relation toV the set on the other, said disks being rotatable and non-tiltable on said spindles.

2'. A knife Sharpener, comprising a frame l having two spaced supporting members, one

of said supporting members having its inner surface receding toward a point centrally between its ends and the other supporting member having its inner surface advanced from its end toward a point centrally between its ends, parallel spindles securedin'said supporting members in spaced relation, and a set of sharpening disks mounted on each spindle and clamped between the recedingand advancing surfaces of said side members, the

two sets of disks being marginally-overlapped with their` peripheral edges at acuteangles to a knife blade being sharpened.

3. A knife Sharpener, comprising a frame having spaced supporting walls, one'of said walls receding along-a portion ofits height from each end thereof to a point centrally a pair of spaced parallel spindles cary dles con ned against tilting movement on said spindles'by said supporting walls, theV marginal portions of each set of sharpening disks overlapping the marginal portions of the other set and the disks of one set being at a slight angle to the disks of the other.

4. A knife Sharpener, comprising a frame having spaced supporting members, parallel disk-supporting spindles extending throughv the space` between said supporting members and carried by the latter, and a set of rotatablyadjustable `disks on each spindle having the disks of each set correspondingly tilted on their supporting spindle and so maintained by said supporting members and the disks of each set marginally overlapping those of the other, saidspaced supporting members lying in contact with the end disks .of each set and being angularly disposed with reference to said spindlesto maintain the disks of both sets in theirl tilted positions.

5. A knife Sharpener having a supporting frame, spaced parallel spindles carried 'by said frame, disks onksaid' spindles having openings of a diameterslightly larger than the diameter of said spindles to permitof tilting the disks on said spindles, and means embodied in the construction of said supporting frame to position and maintain said disks in tilted position.

In testimony whereof I aX my signature.

WILLIAM F. POLSON.

between its ends and the other being advanced K n,

along a kportion of its height from opposite ends thereof to a -point centrally'between its ends, parallel` spindles supported by said 

